System and method for atomic layer deposition of solid electrolytes

Abstract

A method of making an ionically conductive layer for an electrochemical device is disclosed. The method includes the steps of: (a) exposing a substrate to a lithium-containing precursor followed by an oxygen-containing precursor; and (b) exposing the substrate to a boron-containing precursor followed by the oxygen-containing precursor.

What is claimed is: 
     
         1 . A method of making an ionically conductive layer, the method comprising:
 (a) exposing a substrate to a lithium-containing precursor followed by a first oxygen-containing precursor; and   (b) exposing the substrate obtained from step (a) to a boron-containing precursor followed by a second oxygen-containing precursor,   wherein the ionically conductive layer comprises a mixture of Li 2 CO 3  and Li 3 BO 3 ,   wherein the lithium-containing precursor comprises a lithium alkoxide,   wherein the lithium-containing precursor is in a gaseous state,   wherein the first oxygen-containing precursor is selected from the group consisting of ozone, oxygen plasma, ammonium hydroxide, oxygen, and mixtures thereof, and   wherein the second oxygen-containing precursor is selected from the group consisting of ozone, oxygen plasma, ammonium hydroxide, oxygen, and mixtures thereof.   
     
     
         2 . The method of  claim 1  wherein:
 the boron-containing precursor comprises a boron alkoxide. 
 
     
     
         3 . The method of  claim 1  wherein:
 the first oxygen-containing precursor is ozone, and 
 the second oxygen-containing precursor is ozone. 
 
     
     
         4 . The method of  claim 1  wherein:
 the boron-containing precursor, the first oxygen-containing precursor, and the second oxygen-containing precursor are in a gaseous state. 
 
     
     
         5 . The method of  claim 1  wherein:
 the ionically conductive layer has a thickness between 40 and 1000 nanometers. 
 
     
     
         6 . The method of  claim 1  wherein:
 the ionically conductive layer has a total area-specific resistance of less than 450 Ω-cm 2 . 
 
     
     
         7 . The method of  claim 1  wherein:
 the ionically conductive layer has an ionic conductivity of greater than 2.0×10 −6  S/cm. 
 
     
     
         8 . The method of  claim 1  wherein:
 the ionically conductive layer has an ionic transference number of greater than 0.9999 from 0-6 volts vs lithium metal. 
 
     
     
         9 . The method of  claim 1  wherein:
 step (a) and step (b) occur at a temperature between 50° C. and 280° C. 
 
     
     
         10 . The method of  claim 1  wherein:
 the substrate has a planar structure. 
 
     
     
         11 . The method of  claim 1  wherein:
 the substrate has a three dimensional structure. 
 
     
     
         12 . The method of  claim 1  further comprising:
 tuning carbon content in the ionically conductive layer relative to boron content in the ionically conductive layer. 
 
     
     
         13 . A method of making an electrochemical device, the method comprising:
 (a) exposing a substrate to a lithium-containing precursor followed by a first oxygen-containing precursor, wherein the substrate in step (a) is selected from the group consisting of a current collector, an anode, a cathode, and a solid state electrolyte; and   (b) exposing the substrate obtained from step (a) to a boron-containing precursor followed by a second oxygen-containing precursor,   wherein an ionically conductive layer is formed on the substrate obtained from step (b), and   wherein the ionically conductive layer comprises a mixture of Li 2 CO 3  and Li 3 BO 3 ,   wherein the lithium-containing precursor comprises a lithium alkoxide, and   wherein the lithium-containing precursor is in a gaseous state,   wherein the first oxygen-containing precursor is selected from the group consisting of ozone, oxygen plasma, ammonium hydroxide, oxygen, and mixtures thereof, and   wherein the second oxygen-containing precursor is selected from the group consisting of ozone, oxygen plasma, ammonium hydroxide, oxygen, and mixtures thereof.   
     
     
         14 . The method of  claim 13  wherein:
 the boron-containing precursor comprises a boron alkoxide. 
 
     
     
         15 . The method of  claim 13  wherein:
 the boron-containing precursor, the first oxygen-containing precursor, and the second oxygen-containing precursor are in a gaseous state. 
 
     
     
         16 . The method of  claim 13  wherein:
 the ionically conductive layer has a total area-specific resistance of less than 450 Ω-cm 2 . 
 
     
     
         17 . The method of  claim 13  wherein:
 the ionically conductive layer has an ionic conductivity of greater than 2.0×10 −6  S/cm. 
 
     
     
         18 . The method of  claim 13  wherein:
 the ionically conductive layer has an ionic transference number of greater than 0.9999 from 0-6 volts vs lithium metal. 
 
     
     
         19 . The method of  claim 13  further comprising:
 tuning carbon content in the ionically conductive layer relative to boron content in the ionically conductive layer. 
 
     
     
         20 . The method of  claim 13  wherein:
 the first oxygen-containing precursor is ozone, and 
 the second oxygen-containing precursor is ozone. 
 
     
     
         21 . A method of making an electrochemical device, the method comprising:
 (a) exposing a substrate to a lithium-containing precursor followed by a first oxygen-containing precursor; and   (b) exposing the substrate obtained from step (a) to a boron-containing precursor followed by a second oxygen-containing precursor,   wherein an ionically conductive layer is formed on the substrate obtained from step (b), and   wherein the substrate in step (a) is a solid state electrolyte,   wherein the lithium-containing precursor comprises a lithium alkoxide, and   wherein the lithium-containing precursor is in a gaseous state,   wherein the first oxygen-containing precursor is selected from the group consisting of ozone, oxygen plasma, ammonium hydroxide, oxygen, and mixtures thereof, and   wherein the second oxygen-containing precursor is selected from the group consisting of ozone, oxygen plasma, ammonium hydroxide, oxygen, and mixtures thereof.   
     
     
         22 . The method of  claim 21  wherein:
 the solid state electrolyte comprises a material selected from the group consisting of lithium lanthanum titanates, Li 3 OCl (anti-perovskite), Li 14 ZnGe 4 O 16  (LiSICON), Li 1.3 Ti 1.7 Al 0.3 (PO 4 ) 3  (NaSICON type), thio-LiSICON, Li 6 PS 5 X (X=Cl, Br, I), argyrodites, lithium phosphorus sulfides, and Li 10 MP 2 S 12 , (M=Ge, Sn). 
 
     
     
         23 . The method of  claim 21  wherein:
 the solid state electrolyte comprises a ceramic material having a formula of Li w A x M 2 Re 3-y O z ,
 wherein w is 5-7.5, 
 wherein A is selected from B, Al, Ga, In, Zn, Cd, Y, Sc, Mg, Ca, Sr, Ba, and any combination thereof, 
 wherein x is 0-2, 
 wherein M is selected from Zr, Hf, Nb, Ta, Mo, W, Sn, Ge, Si, Sb, Se, Te, and any combination thereof, 
 wherein Re is selected from lanthanide elements, actinide elements, and any combination thereof, 
 wherein y is 0-0.75, 
 wherein z is 10.875-13.125, and 
 wherein the material has a garnet-type or garnet-like crystal structure. 
 
 
     
     
         24 . The method of  claim 21  wherein:
 the first oxygen-containing precursor is ozone, and 
 the second oxygen-containing precursor is ozone.